The article discusses the emerging field of underwater Internet of Things (IoT) technology, which is enabling new possibilities for ocean research and connectivity. Underwater IoT systems consist of networks of sensors and communication devices that can operate beneath the surface, transmitting data wirelessly through water. These systems are being used to monitor ocean conditions, track marine life, and even facilitate underwater communications. Key points include: 1) Underwater IoT expands the reach of ocean research by allowing data collection in remote areas. 2) It enables real-time monitoring of ocean environments and ecosystems. 3) Acoustic modems and sensors form the backbone of underwater IoT networks. 4) Challenges include limited bandwidth, signal attenuation, and power constraints. 5) Applications span environmental monitoring, offshore energy, maritime security, and disaster prevention. The article concludes that underwater IoT is a rapidly evolving field with significant potential to advance our understanding and stewardship of the world’s oceans.